Mixing valves used for mixing two fluids for sanitary fixtures, particularly warm and cold water, can comprise a valve seat disk having two inlet passage openings and a controlling disk held against the valve seat disk and adjustable by a handle, so that the relative proportions of the fluids mixed are controllable by rotation of the controlling disk, and the total flow rate of the mixed fluid is controlled by a somewhat linear displacement of the controlling disk.
The two inlet passage openings for the fluids to be mixed are formed symmetrically in one half of the valve seat disk. Each of the two passage openings is formed as an arcuate segment on a circular arc. Transfer passage formed in the controlling disk is brought into overlapping relationship with the inlet passage openings adjacent an arc shaped front edge of the transfer passage.
In mixing valves used to control the water temperature in a sanitary fixture it is essential between the extreme "cold" and "hot" positions to have a comparatively large range of swing or pivot angle for the "comfort" temperature range of between 30.degree. to 45.degree. C. With these valves the temperature range can easily be brought close to the body temperature of the user and comparatively exactly controlled, but even slight deviations of from 1.degree. C. to 2.degree. C. from the desired temperature are noticeable.
In the known mixing valves, the adjustment of the relative proportion of the mixed fluids, e.g. cold and warm water, is substantially proportional to the rotational angle of the handle , so that in a total pivot angle or swing of say 110.degree. only a pivot angle of about 20.degree. is available for a mixed water temperature range of from 30.degree. to 45.degree. C. and thus sensitive fine adjustment is made only with difficulty.
German Patent DE-OS No. 32 44 121 describes a mixing valve in which a more sensitive fine adjustment of the relative proportions of the fluids mixed is attained in the preferred temperature range. In this mixing valve structure the rotation axis of the controlling disk is arranged eccentric to the valve seat disk axis. Therefore, among other requirements the valve housing must be constructed with supporting receptacles eccentric to each other for the valve seat disk and the controlling disk.